Circadian Rhythm And Time-dependent Effects Of Aspirin On Platelet Activity In Hypertensive Patients

Objectives: We detect the levels of the platelet surface glycoprotein IIb/IIIa receptor(PAC-1) and P-selectin(CD62P) to explore the circadian differences of platelet activiation in hypertensive patients. The patients with hypertension was also be observed the time-dependent effects of aspirin on platelet activity circadian.Methods: We detect the expression levels of PAC-1 and CD62 P on platelet surface in hypertensive patients and health people at night and early in morning.Results : The levels of PAC-1 and CD62 P on platelet surface early in morning compared with the levels at night were significant increased in health people and hypertensive patients. The platelet activity in hypertensive patients were increased compared with health people. But the platelet activity in hypertensive patients taking aspirin at bedtime was no significant difference between the morning and night. In hypertensive subgroups, the levels of PAC-1 in the patients taking aspirin on awakening compared with no taking aspirin were reduced both in the morning and at night, but the levels of CD62 P in these patients decreased only at night. The levels of PAC-1 in the patients taking aspirin at bedtime compared with no taking aspirin were reduced both in the morning and at night, but the levels of CD62 P in these patients decreased only early in morning. Compared with the patients taking aspirin on awakening, the platelet activity of the patients taking aspirin at bedtime was reduced early in morning only.Conclusions: The platelet activity of the hypertensive patients has circadian rhythm.Bedtime aspirin intake reduced the platelet activity in the morning and the morning peak phenomenon of adverse cardiovascular events.